338 CALIFORNIA ACADEMY OP SCIENCES. 



Origin of veiitrals equidistant from tip of caudal and 

 tip of snout, or a little nearer tip of caudal; their tips 

 reaching to the vent. 



Brownish, lighter below; fins somewhat dusky; speci- 

 men from Sao Matheos uniform blackish brown. 



Head 5J-5J (6-6J in total); D. 11; A. 9. 



271, Pygidium taczanowskii, 



Trichomycterus taczanowskii Steindachner, Flussfische Sudani, iv, 

 22, pi. iv, figs. 1-16, 1882 (Kio de Huambo; Kio de Tortora). 



Pygidium taczanowskii E. & E. Proc. Cal. Acad. Sci. 2d Ser. ii, 52, 

 1889. 



Habitat: Andes of Peru. 



272, Pygidium nigricans. 



Trichomycterus nigricans Cuv. & Val. Hist. Nat. Poiss. xviii, 494, 

 1846 (Santa Catharina); ? Gay, Hist. Chile, 311, 1848 (Chile); 

 Giinther, Cat. Fish. Brit. Mus. v, 274, 1864 (copied). 



Pygidium nigricans Eigenm. & Eigenm. Proc. Cal. Acad. 2d Ser. ii, 

 53, 1889. 



Habitat: Santa Catharina. 



273, Pygidium amazonicum, 



Trichomycterus amazonicum Steindachner, Flussf. Sudani, iv, 29, 



pi. vi, figs. 4-4a, 1882 (Cudajas). 

 Pygidium amazonicum Eigenm. & Eigenm. Proc. Cal. Acad. Sci. 2d 



Ser. ii, 53, 1889. 

 Habitat: Amazon near Cudajas. 



LXI. EREMOPHILUS. 



Eremophilus Humboldt, Rec. d'Obs. Zool. et Anat. i, 

 17, pi. 6, 1811 (mutisii). 



Thrichomycterus Humboldt, 1. c. (alternative of ere- 

 mophilus). 



Trachypoma Giebel, " Z. Ges. Ntrw. iii, 97, 1871" 

 (marmoratum= mutisii) . 



Type: Eremophilus mutisii Humboldt. 



This genus differs from Pygidium in having no ven- 

 tral fins. 



